// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/process/process_metrics.h"

#include <utility>

#include "base/logging.h"
#include "base/values.h"
#include "build/build_config.h"

namespace base {

SystemMetrics::SystemMetrics()
{
    committed_memory_ = 0;
}

SystemMetrics SystemMetrics::Sample()
{
    SystemMetrics system_metrics;

    system_metrics.committed_memory_ = GetSystemCommitCharge();
#if defined(OS_LINUX) || defined(OS_ANDROID)
    GetSystemMemoryInfo(&system_metrics.memory_info_);
    GetSystemDiskInfo(&system_metrics.disk_info_);
#endif
#if defined(OS_CHROMEOS)
    GetSwapInfo(&system_metrics.swap_info_);
#endif

    return system_metrics;
}

std::unique_ptr<Value> SystemMetrics::ToValue() const
{
    std::unique_ptr<DictionaryValue> res(new DictionaryValue());

    res->SetInteger("committed_memory", static_cast<int>(committed_memory_));
#if defined(OS_LINUX) || defined(OS_ANDROID)
    res->Set("meminfo", memory_info_.ToValue());
    res->Set("diskinfo", disk_info_.ToValue());
#endif
#if defined(OS_CHROMEOS)
    res->Set("swapinfo", swap_info_.ToValue());
#endif

    return std::move(res);
}

ProcessMetrics* ProcessMetrics::CreateCurrentProcessMetrics()
{
#if !defined(OS_MACOSX) || defined(OS_IOS)
    return CreateProcessMetrics(base::GetCurrentProcessHandle());
#else
    return CreateProcessMetrics(base::GetCurrentProcessHandle(), nullptr);
#endif // !defined(OS_MACOSX) || defined(OS_IOS)
}

double ProcessMetrics::GetPlatformIndependentCPUUsage()
{
#if defined(OS_WIN)
    return GetCPUUsage() * processor_count_;
#else
    return GetCPUUsage();
#endif
}

#if defined(OS_MACOSX) || defined(OS_LINUX)
int ProcessMetrics::CalculateIdleWakeupsPerSecond(
    uint64_t absolute_idle_wakeups)
{
    TimeTicks time = TimeTicks::Now();

    if (last_absolute_idle_wakeups_ == 0) {
        // First call, just set the last values.
        last_idle_wakeups_time_ = time;
        last_absolute_idle_wakeups_ = absolute_idle_wakeups;
        return 0;
    }

    int64_t wakeups_delta = absolute_idle_wakeups - last_absolute_idle_wakeups_;
    int64_t time_delta = (time - last_idle_wakeups_time_).InMicroseconds();
    if (time_delta == 0) {
        NOTREACHED();
        return 0;
    }

    last_idle_wakeups_time_ = time;
    last_absolute_idle_wakeups_ = absolute_idle_wakeups;

    // Round to average wakeups per second.
    int64_t wakeups_delta_for_ms = wakeups_delta * Time::kMicrosecondsPerSecond;
    return (wakeups_delta_for_ms + time_delta / 2) / time_delta;
}
#else
int ProcessMetrics::GetIdleWakeupsPerSecond()
{
    NOTIMPLEMENTED(); // http://crbug.com/120488
    return 0;
}
#endif // defined(OS_MACOSX) || defined(OS_LINUX)

} // namespace base
